NASA's 2001 Mars Odyssey gave mission managers a real treat this Halloween with its first look at the red planet. It's a thermal infrared image of the martian southern hemisphere that captures the south polar carbon dioxide ice cap at a temperature of about minus 120 C (minus 184 F).

The spacecraft first entered orbit around Mars last week after a six-month, 460- million-kilometer (285-million-mile) journey.

The image, taken as part of the calibration and testing process for the instrument, shows the nighttime temperatures of Mars, demonstrating the "night-vision" capability of the camera system to observe Mars even when the surface is in darkness.

"This spectacular first image of Mars from the 2001 Mars Odyssey spacecraft is just a hint of what's to come," said Dr. Ed Weiler, associate administrator for space science at NASA Headquarters in Washington, D.C. "After we get Odyssey into its final orbit it will be much closer to Mars than when it took this image, and we'll be able to tell whether or not there are any hot springs on Mars, places where liquid water may be close to the surface. If there are any such locations they would be places we might like to explore on future missions."

The image covers a length of more than 6,500 kilometers (3,900 miles), spanning the planet from limb to limb, with a resolution of approximately 5.5 kilometers per pixel (3.4 miles per pixel), at the point directly beneath the spacecraft.

The spacecraft was approximately 22,000 kilometers (about 13,600 miles) above the planet looking down toward the south pole of Mars when this image was taken.

It is late spring in the martian southern hemisphere. The extremely cold, circular feature shown in blue is the martian south polar carbon dioxide ice cap , which is more than 900 kilometers (540 miles) in diameter at this time and will continue to shrink as summer progresses. Clouds of cooler air blowing off the cap can be seen in orange extending across the image.

The Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science. The thermal-emission imaging system was developed at Arizona State University, Tempe, with Raytheon Santa Barbara Remote Sensing, Santa Barbara, Calif. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.